Merge pull request #2911 from retronym/ticket/7814

SI-7814 Avoid init cycle between Predef, `package`, ScalaRuntime

1 files changed, 31 insertions, 35 deletions

diff --git a/src/library/scala/runtime/ScalaRunTime.scala b/src/library/scala/runtime/ScalaRunTime.scala
index 1d8fe5e9ad..dcd323961e 100644
--- a/src/library/scala/runtime/ScalaRunTime.scala
+++ b/src/library/scala/runtime/ScalaRunTime.scala
@@ -34,21 +34,13 @@ object ScalaRunTime {
     clazz.isArray && (atLevel == 1 || isArrayClass(clazz.getComponentType, atLevel - 1))
 
   def isValueClass(clazz: jClass[_]) = clazz.isPrimitive()
-  def isTuple(x: Any) = x != null && tupleNames(x.getClass.getName)
+
+  // includes specialized subclasses and future proofed against hypothetical TupleN (for N > 22)
+  def isTuple(x: Any) = x != null && x.getClass.getName.startsWith("scala.Tuple")
   def isAnyVal(x: Any) = x match {
     case _: Byte | _: Short | _: Char | _: Int | _: Long | _: Float | _: Double | _: Boolean | _: Unit => true
     case _                                                                                             => false
   }
-  // Avoiding boxing which messes up the specialized tests.  Don't ask.
-  private val tupleNames = {
-    var i = 22
-    var names: List[String] = Nil
-    while (i >= 1) {
-      names ::= ("scala.Tuple" + String.valueOf(i))
-      i -= 1
-    }
-    names.toSet
-  }
 
   /** Return the class object representing an array with element class `clazz`.
    */
@@ -75,33 +67,37 @@ object ScalaRunTime {
     classTag[T].runtimeClass.asInstanceOf[jClass[T]]
 
   /** Retrieve generic array element */
-  def array_apply(xs: AnyRef, idx: Int): Any = xs match {
-    case x: Array[AnyRef]  => x(idx).asInstanceOf[Any]
-    case x: Array[Int]     => x(idx).asInstanceOf[Any]
-    case x: Array[Double]  => x(idx).asInstanceOf[Any]
-    case x: Array[Long]    => x(idx).asInstanceOf[Any]
-    case x: Array[Float]   => x(idx).asInstanceOf[Any]
-    case x: Array[Char]    => x(idx).asInstanceOf[Any]
-    case x: Array[Byte]    => x(idx).asInstanceOf[Any]
-    case x: Array[Short]   => x(idx).asInstanceOf[Any]
-    case x: Array[Boolean] => x(idx).asInstanceOf[Any]
-    case x: Array[Unit]    => x(idx).asInstanceOf[Any]
-    case null => throw new NullPointerException
+  def array_apply(xs: AnyRef, idx: Int): Any = {
+    xs match {
+      case x: Array[AnyRef]  => x(idx).asInstanceOf[Any]
+      case x: Array[Int]     => x(idx).asInstanceOf[Any]
+      case x: Array[Double]  => x(idx).asInstanceOf[Any]
+      case x: Array[Long]    => x(idx).asInstanceOf[Any]
+      case x: Array[Float]   => x(idx).asInstanceOf[Any]
+      case x: Array[Char]    => x(idx).asInstanceOf[Any]
+      case x: Array[Byte]    => x(idx).asInstanceOf[Any]
+      case x: Array[Short]   => x(idx).asInstanceOf[Any]
+      case x: Array[Boolean] => x(idx).asInstanceOf[Any]
+      case x: Array[Unit]    => x(idx).asInstanceOf[Any]
+      case null => throw new NullPointerException
+    }
   }
 
   /** update generic array element */
-  def array_update(xs: AnyRef, idx: Int, value: Any): Unit = xs match {
-    case x: Array[AnyRef]  => x(idx) = value.asInstanceOf[AnyRef]
-    case x: Array[Int]     => x(idx) = value.asInstanceOf[Int]
-    case x: Array[Double]  => x(idx) = value.asInstanceOf[Double]
-    case x: Array[Long]    => x(idx) = value.asInstanceOf[Long]
-    case x: Array[Float]   => x(idx) = value.asInstanceOf[Float]
-    case x: Array[Char]    => x(idx) = value.asInstanceOf[Char]
-    case x: Array[Byte]    => x(idx) = value.asInstanceOf[Byte]
-    case x: Array[Short]   => x(idx) = value.asInstanceOf[Short]
-    case x: Array[Boolean] => x(idx) = value.asInstanceOf[Boolean]
-    case x: Array[Unit]    => x(idx) = value.asInstanceOf[Unit]
-    case null => throw new NullPointerException
+  def array_update(xs: AnyRef, idx: Int, value: Any): Unit = {
+    xs match {
+      case x: Array[AnyRef]  => x(idx) = value.asInstanceOf[AnyRef]
+      case x: Array[Int]     => x(idx) = value.asInstanceOf[Int]
+      case x: Array[Double]  => x(idx) = value.asInstanceOf[Double]
+      case x: Array[Long]    => x(idx) = value.asInstanceOf[Long]
+      case x: Array[Float]   => x(idx) = value.asInstanceOf[Float]
+      case x: Array[Char]    => x(idx) = value.asInstanceOf[Char]
+      case x: Array[Byte]    => x(idx) = value.asInstanceOf[Byte]
+      case x: Array[Short]   => x(idx) = value.asInstanceOf[Short]
+      case x: Array[Boolean] => x(idx) = value.asInstanceOf[Boolean]
+      case x: Array[Unit]    => x(idx) = value.asInstanceOf[Unit]
+      case null => throw new NullPointerException
+    }
   }
 
   /** Get generic array length */